Question

Differentiate between oestrus and menstrual cycles. Cite an example for each type.

Answer 1

The difference between oestrus and menstrual cycle are as follows

	Oestrus cycle	Menstrual cycle
1.	The cyclic changes in the activities of ovaries and accessory ducts as well as hormones during the reproductive phase of non-primate mammals is called oestrus cycle.	The cyclic changes in the activities of ovaries, and accessory ducts as well as hormones during the reproductive phase of primate mammals is called menstrual cycle.
2.	Females show strong irresistible sexual urge.	Females do not show irresistible sexual urge.
3.	There is estrus/heat production at the time of ovulation and copulation occurs only at that period.	There is no heat period and copulation occurs during any time of the cycle.
4.	The shedding of endometrium and bleeding do not occur. e.g., cows, sheep, rats, deers, dogs and tigers etc.	The shedding of endometrium and bleeding occurs. e.g., monkeys, apes and humans.